: This is a "quality value" or weight. It ranges from 0.0 to 1.0. A value of 0.9 indicates a very high preference for this language, usually as a second choice after a primary language (like English). How It Works in Practice
When you visit a website, your browser sends a header that might look like this: Accept-Language: en-US,en;q=0.9,sr-RS;q=0.8 In this example: 0.9,sr-RS
: Some advanced users modify these strings to make their browser fingerprint less unique, though this is less common for standard languages like Serbian. : This is a "quality value" or weight
: It ensures users see content in a language they understand without having to manually select it. 0.9,sr-RS